diff --git a/thu_learn_downloader/client/learn.py b/thu_learn_downloader/client/learn.py
index f91896a..2ca2dc7 100644
--- a/thu_learn_downloader/client/learn.py
+++ b/thu_learn_downloader/client/learn.py
@@ -1,13 +1,15 @@
 import functools
 import re
+from playwright.sync_api import sync_playwright
+from requests.cookies import RequestsCookieJar
 from collections.abc import Sequence
+from urllib.parse import ParseResult
 
 from bs4 import BeautifulSoup, Tag
-from playwright.sync_api import sync_playwright
 from requests import Response
-from requests.cookies import RequestsCookieJar
 
 from thu_learn_downloader.common.typing import cast
+
 from . import url
 from .client import Client, Language
 from .semester import Semester